Drawing on the theory of the Big Two content dimensions of social judgmentagency and communionthe author proposes that several findings about partisan differences in the United States can be integrated into one hypothesis: Republicans tend to put greater value on agency, while Democrats put greater value on communion. Moreover, on the basis of these values, Republicans and Democrats should judge their own groups as particularly superior on agency and communion, respectively. These hypotheses gained support in three studies on partisan values and ingroup bias, suggesting that the agency-communion framework may be useful for researchers studying how political groups differ in their worldviews, biases, and attitudes.